WEDNESDAY, July 11, 2012 (HealthDay News) -- An HIV drug significantly reduced the risk of graft-versus-host disease, an all-too-common complication in blood cancer patients following bone marrow transplants, new research finds.
Bone marrow is the spongy tissue inside the bones that contains immature cells, or stem cells. In an "allogeneic" bone marrow transplantation, also called a stem cell transplant, a patient's own stem cells and immune system are wiped out by chemotherapy and radiation. Then, the patient receives the transplant, or bone marrow, from a closely matched donor.
The treatment is used for several types of blood cancers, including lymphoma and leukemia.
But a common complication of a bone marrow transplant is graft-versus-host disease. It occurs when transplanted immune cells attack patients' healthy tissue, a complication that can be minor or life-threatening.
"Graft-versus-host disease affecting the skin, liver, gut and other organs is a dreaded complication of allogeneic stem cell transplantation either from a related or unrelated donor," said one expert, Dr. Jasmine Zain of NYU Langone Medical Center in New York City. "The rates are 35 percent with related donors and up to 57 percent by day 100, even in reduced-intensity transplants," added Zain, who is director of the Bone Marrow Transplant Program and assistant professor in the division of hematologic malignancies and medical oncology at the center.
The study was conducted by a team at the University of Pennsylvania's Perelman School of Medicine and included 38 patients with several types of blood cancers. The cancers included acute myeloid leukemia, myelodysplastic syndrome, lymphoma and myelofibrosis. All of the patients were given the drugs tacrolimus and methotrexate, which suppress the immune system and are a standard treatment to prevent graft-versus-host disease.
The patients were also given a 33-day course of the HIV drug, maraviroc, beginning two days before their transplant.
None of the patients treated with maraviroc developed graft-versus-host disease in the gut or liver within the first 100 days after their transplant. The liver and gut are the most serious locations for the complication, the researchers noted.
After six months, 6 percent of these transplant patients developed severe graft-versus-host disease compared to 22 percent of a group of similar patients who weren't treated with the HIV drug.
In addition, fewer in the group given the HIV drug developed graft-versus-host disease in their liver or gut compared to those given the standard treatment.
One year following transplant, about 15 percent of patients given the HIV drug developed severe graft-versus-host disease compared to 29 percent of patients who received standard therapy.
The study was published in the July 11 edition of the New England Journal of Medicine.
Researchers explained that the HIV drug redirects these immune cells without having to suppress patients' immune systems. Because their immune systems aren't compromised by the drug, patients should be less vulnerable to infections and to a relapse of their cancer.
"It appears that our new approach allows us to prevent some patients from developing [graft-versus-host disease] by redirecting immune cells away from certain sensitive organs that they could harm," lead study author Dr. Ran Reshef, an assistant professor in the division of hematology-oncology, said in a university news release. "This is a novel way for us to try to decrease treatment-related complications among bone marrow transplant patients without also reducing their new immune system's ability to attack their cancer."
More research on the effects of longer-term treatment with maraviroc is needed, they added.
For her part, Zain called the study "innovative."
"There was no increase in the degree of immunosuppression, which is the usual approach to prevent and treat graft-versus-host disease but comes at a cost of increased infections and disease relapse," Zain said. "This makes this a novel and unique approach that should be investigated in a larger trial."
More information
The U.S. National Library of Medicine has more about bone marrow transplants.
